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Wetlands

Alkaline Wetlands

/portal_images/wetlands/content_images/AlkalineWetlandsGreasewood.jpg

Greasewood and saltgrass flat, Warner Valley, Lake County
(John A. Christy, PSU Oregon Biodiversity Information Center)

Alkaline wetlands are restricted to arid lands east of the Cascade Range. They include seasonally or intermittently flooded playas, marshes, and lakes, where alkaline soils and intense evaporation tend to concentrate salts in soils and water. They may support large populations of plants and animals found nowhere else in arid regions, and in Oregon they are particularly well known as breeding or foraging sites for vast quantities of migrating birds. Many of the same species of plants and animals occur in both interior alkaline wetlands and estuarine wetlands along the coast, and the term "brackish marsh" has been applied to both. Playas or "salt flats" occur in basins with interior drainage that lack any exit streams. During years of high precipitation, runoff and meltwater accumulate in valley bottoms or depressions. Small to large, shallow lakes may form, or existing lakes may expand to flood areas around their edges. Playas are dependent on regional climatic cycles, and their flooding is by definition intermittent and often fleeting. Water may persist into the growing season for a few weeks, a month, or rarely years, and sites may not flood at all for years at a time. Playas are typified by flat topography, highly alkaline or saline soils, and no or scant vegetation that is distinctive and adapted to saline or alkaline conditions. Animals are adapted to the intermittent hydrology and may emerge only every few years when conditions are right.

Alkaline Wetland Map

Alkaline Wetland

Habitat: Basins and flats, edges of alkaline lakes and ponds, playas
Water regime: Perennially to seasonally flooded
Water chemistry: Saline or alkaline

Ecoregion*: BM = Blue Mountains, BR = Northern Basin and Range, CB = Columbia Basin, CR = Coast Range, EC = East Cascades, KM = Klamath Mountains, WC = West Cascades, WV = Willamette Valley  
Scientific & Common Name Global & State Rank Ecoregion
wetland type image https://nrimp.dfw.state.or.us/DataClearinghouse/default.aspx?p=202&XMLna... Allenrolfea occidentalis Shrubland
Iodine bush
G3S2 BR
wetland type image Artemisia cana ssp. bolanderi / Eleocharis palustris Shrubland
Silver sagebrush / common spikerush
G3S2 BM, BR
wetland type image Artemisia cana ssp. bolanderi /Muhlenbergia richardsonis Shrub Herbaceous Vegetation
Silver sagebrush / common spikerush
G3S3 BR
wetland type image Artemisia cana ssp. viscidula / Deschampsia caespitosa Shrubland
Silver sagebrush / tufted hairgrass
G2S2 BM
wetland type image Atriplex confertifolia - Sarcobatus vermiculatus Shrubland
Shadscale - black greasewood
G5S3 BR
wetland type image Eleocharis rostellata Herbaceous Vegetation
Beaked spikerush
G3S3 BR
wetland type image Distichlis spicata Herbaceous Vegetation
Saltgrass (interior alkaline)
G5S4 CP, BM, BR
wetland type image Distichlis spicata - (Scirpus nevadensis)Herbaceous Vegetation
Saltgrass - (Nevada bulrush)
G4S4 BM, BR
wetland type image Lepidium davisii Herbaceous Vegetation [Provisional]
Davis pepperweed
G3S1 BR
wetland type image Leymus cinereus Herbaceous Vegetation
Giant wildrye
G1S1 BM, BR, CP, EC
wetland type image Leymus cinereus - Distichlis spicata Herbaceous Vegetation
Giant wildrye - saltgrass
CP, BR
wetland type image Leymus triticoides - Poa secundaHerbaceous Vegetation
Creeping wildrye - alkali bluegrass
G2S2 BR
wetland type image Puccinellia lemmonii - Poa secunda Seasonally Flooded Herbaceous Vegetation
Lemmon's alkali grass - Curly bluegrass Giant wildrye
G1S1 BM, BR, EC
wetland type image Sarcobatus vermiculatus / Achnatherum hymenoides Shrubland
Greasewood /Indian ricegrass
G4S3 BR
wetland type image Sarcobatus vermiculatus / Atriplex confertifolia - (Picrothamnus desertorum, Suaeda moquinii) Shrubland
Greasewood / shadscale - (bud sagebrush, shrubby seepweed)
G5S3 BR
wetland type image Sarcobatus vermiculatus / Distichlis spicataShrubland
Greasewood / saltgrass
G4S4 BR
wetland type image Sarcobatus vermiculatus / Leymus cinereus Shrubland
Black greasewood / giant wildrye playa
G3S2 BR
wetland type image Sarcobatus vermiculatus / Nitrophila occidentalis - Suaeda moquinii Shrubland
Black greasewood / borax weed - bushy seablite
G5S5 BR
wetland type image Sarcobatus vermiculatus / Suaeda moquinii Shrubland
Greasewood / seablite playa
G4S4 BR
wetland type image Schoenoplectus acutusHerbaceous Vegetation
Hardstem bulrush
G5S5 BR
wetland type image Schoenoplectus americanusWestern Herbaceous Vegetation (interior alkaline)
Chairmaker's bulrush playa (interior alkaline)
G3S3 BM, BR, CP, EC
wetland type image Schoenoplectus maritimus (interior alkaline) Herbaceous Vegetation
Alkali bulrush
G4S4 BR
wetland type image Schoenoplectus pungens Herbaceous Vegetation (interior alkaline)
Three-square bulrush (interior alkaline)
G3S3 BR
wetland type image Spartina gracilis Herbaceous Vegetation
Alkali cordgrass
G3S2 BM
wetland type image Spartina pectinata Western Herbaceous Vegetation
Prairie cordgrass
G3S2 BM, CP
wetland type image Sporobolus airoides - Distichlis spicata Herbaceous Vegetation
Alkali saltgrass - alkali sacaton
G4S3 BR

Authored by John A. Christy, Wetlands Ecologist, (ORBIC) Oregon Biodiversity Information Center (2012)